OK, you may of tried to learn how to make an animated picture, like in your profile on Newgrounds, or maybe your signature on here.
It's easy, so just create your animation - in Flash MX (no actionscript can be used!), then go:
File>> Publish Settings
then mark .'gif', and go the .gif properties, over the list, then change it from static to animated.
Preview:
File>> Publish preview>> GIF
If its all ok, leave it like that. Now, save the .fla, and do the publish preview again, and now you'll find your animated .gif, where you've saved you fla.
But remember, don't make it too long otherwise it will be slow.
Tutorial by: Johan Peter Kraugerud